Froth-flotation concentration of ores



Patented Mar. 21, 1933 UNITED STATES PATENT orncu' .v

PERCY c. wear, or rmsnu'ao, earn-0am assmnoa r0 11mm summon NORTH LANDraorn-rnorarron concmaarron or one No Drawing.

This invention relates to the froth-flotation concentration of ores andis herein illustrated as applied to the concentration of ores by the aidof an organic disulphide, that is a comgarded as a combination of twomolecules of a salt of xanthic acid in which the removal of the base hasled to the union of the disrupted molecules, the unsatisfied afiinity ofeach disrupted molecule being satisfied by its union with the otherdisrupted molecule. Its formula is structurally written as follows:

H-tJ-H H-(J-Ii ir- -n H- -n The seventh to the fourteenth examples,

inclusive, are of procedures in which other organic disulphides are usedto efiect frothflotation ore concentration, in acid, alkaline andneutral pulps, and the processes of these examples, although embodyingthe present invention in its broad aspect, are not specifically claimedherein.

Dixanthogen is easily produced from sodium and potassium xanthates by atreatment with a substance which will abstract Mlddl the sodium orpotassium from the molecules with the resultant production ofdixanthogen. Among such substances are'chlorine, bromine, andiodine; Itis not always necessary that such materials be free or that the reactiontake place in strong solutions. Satisfactory results have been obtainedby adding chlorine or chloride of lime inflpproximately thetheoretically required amounts to Application filed July 14,

1926. Serial 1T0. 188,486.

pine oil and cresylic acid in the presence of dixanthogen produceconcentrates of'extraordinary richness and tend to float many cop-AMERICAN CORPORATION, OF NEW YORK, N. Y A CORPORATION 01' IABY- It isfound that frothing agents such as per, silver, lead and zinc mineralsto the ex- Y clusion of iron minerals, thus exercising a selectivefiotative action.

Dixanthogen, as illustrated by the first two of the following examples,is especially use-' iul in alkaline pulps. The third example shows italso to be useful in a neutral pulp. It has also been foundto'beuseful-in acid pulps.

The first, second, third and fourth examples show the utility ofdixanthogen which has been separately repared and thereafter added tothe ore pu p. This specific procedure embodying the present invention inits broad aspect is not claimed herein. The fifth and sixth examples areof procedures whereindixanthogen is produced in situ, and suchprocedures are s ecifically claimed herein.

Example 1.-'- uitably ground ore from Utah Copper Company wasagitated-in an aqueous pulp with 4 pounds of lime, and there'was added amixture of equal proportions of dixanthogen and pine'oil in the totalamount of 0.4 pounds, all per ton of ore, and the agitation continued toyield a. concentrate, middling and tailing. The results were as follows:

Assay Recoveries Product Cu Fe Cu Fe 93 Example 2.Suitably ground orefrom Inspiration Copper Company was agitated in an aqueous pulp with 3pounds of lime, and there was added a mixture of equal proportions ofdixanthogen and pine oil in the total amount of 0.4 pounds, all per tonof ore, and the agitation continued to yield a concentrate, a middlingand a tailing. Theresults, showing extraordinary richness of theconcentrate, were as'follows:

5 Assay Recoveries Product Cu Fe Cu Fe Example 3.Suitahly groundCalifornia Rand gold-silver ore was agitated in an aqueous pulp with 0.2pounds of dixanthogen mixed with an equal quantity of pine oil, per tonof ore, to yield a concentrate, a middling and a tailing. The resultsare shown in the following table: 5

were agitated in an aqueous pulp with a mixture in equal proportions ofdixanthogen and pine, oil in the total amount of 0.4 pounds per ton ofsolids, to yield a finished concentrate. The pulp had previously beenmade alkaline Exam Ze' 6.--Another portion of similarly describa 1emiddlings was agitated in an aqueous pulp with 0.25 pounds of potassiumxanthate and 0.2 pounds of pine oil, both per .ton of the solids, andthen there was passed into the pulp about 0.0610 0.07 pounds of chlorinegas, per ton of solids, from a storage cylinder. Agitation was continuedto yield a finished concentrate. lhe richness of the concentrate and theother results are shown in the following table:

Assays Recover- 7 Zn ieS Zn Heads 38.1 100.0

Cnnmnh tn 59.8 83.0

Tails 10. 5 12.

Ezra/mp3s 7.Utah copper impact screen undersize was reground with 0.pounds of ethyl-disulphide per ton and then agitated in an aqueous pulpfor ten minutes with 0.25 pounds of cresol per ton. The results areshown in the following tahle:

Assays Recoveries Product Wt. on Fe Cu Fe Example 8.-Utah copper impactscreen undersize was reground with 6 pounds of cal cium'oxide and with0.4 pounds of ethyl-diwith 3 pounds of lime per ton of solids. hesulphide per ton and then agitated for ten results are shown in thefollowing table: mmutes In n aqueous pulp wlth 0.4 pounds of cresol perton. The results-are shown in t bl Am 5 Renew the rollowing ca e. 4.0Rogue; Zn eries Assays Recoveries Heads 38. 1 160 pmduct Concentrs 57.480 Tells 12.5 11 %Wt. Cu Fe Cu Fe Eauam Ze5.- -Another portiox rofsirnilarly 3l ssas::::::::::::: ith 2th it? 83:? describe le mlddhngswas agitated in an T3118 9- J4 Assays Recoveries Product 5 Zn Fe Zn FeEmample 9.Utah copper impact screen undersize was reground with 6 poundsof calcium oxide per ton and agitated for ten minutes in an aqueous pulpwith 0.4 pounds per ton of a 20% solution of ethyl-disulphide incresoltogether with an additional 0.3 pounds of cresol per ton. Theresults are shown in the following table:

- Assays Recoveries Product Wt. Cu Fe Cu Fe Ewample 10.-Utah copper orewas agitated in anaqueous pulp with 14.8 pounds of recast? sulphuricacid per ton of ore and with a small I quantity of pine oil and 0.21pounds of isoamyl-disulphide per ton of ore. A concentrate was obtainedcarrying 9.3% of copper and 26.3% of iron and containing the desiredamount, 34.4% of insolubles. This left a tailing containing 0.11% ofcopper and represented a recovery of 90.5% of the copper in the ore.

1 Sometimes an exceedingly small proportion of a disulphide is extremelyefi'ectiye as in the following example:

Example 11.Utah copper impact screen undersize was reground with 6pounds of calcium oxide per ton of ore and agitated in an aqueous pulpwith 0.4 pounds of a soluamount of pine oil and paraflin gas 'tion' ofphenyl-disulphide in. cresol per ton of ore. The results are shownin-the followmg table:

Assays Recoveries Product Wt. Cu Fe Cu Fe (is 1011.0 1.32 1.65 10110100.11 Concentrate am 19.84 10.3 9011 31.5"

When a larger amount of phenyl-disulphide was used a somewhat richerconcentrate was obtained with an increased content of iron and a veryslightly diminished recovery of the copper of the ore.

Ewample 12.Anaconda table tailings were agltated in an aqueous pulp with12 pounds of sulphuric acid per ton of solids and with a small amount ofpine oil and with paraflin s distillate and with 0.23 unds ofn-amylisulphide per ton of soli After re-treatment a concentrate wasobtained containing 10.8% of copper and 30.5% of iron and carrying 12.3%of insolubles. The tailings carried 0.8% ofcopper representing areclovery of 82.5% of the copper 1n the materia Example 13.A repetitionof the latter procedure substituting carbonate of soda for the acid andomitting the paraflin gas distillmentsof the invention, what is claimedis:

1. The process of concentrating ores which consists in mixing anxanthate and another wfroth.

In testimony whereof, I have aflixed my representing a. re-

material inan ore pulp so as to yield dixanthogen, agitating the pulp soas to produce a mineral-bearing frot froth. v v

2. The process of concentrating ores which consists in mixing in an orepulp an alkaliand separating the v metal xanthate with a substanceadapted to react therewith to produce dixanthogen, agitating the pulpwith a mineral-frothin agent to produce a mineral-bearing froth, anseparating the froth. k 3. The process of concentrating ores whichconsists in mixing with an ore pulp a mineral-= frothing agent in thepresence of available chlorine and an xanthate so as to producedixanthogen, agitating the pulp to form a' mineral-bearing froth, andseparating the froth.

eral-frothing agent, in the presence of chloride of lime and an xanthateso as to produce dixanthogen, agitating the pulp to form amineral-bearing froth, and separating the signature tothisspecification.

PERCY C. WRIGHT.

4. The process of concentrating ores which consists in .mixing with anore pulp a minizo

